This application requests support for the development of an "Owl Monkey (Aotus spp.) Breeding and Research Resource" (OMBRR) that will expand our work with New World Monkeys and be complementary to the "Squirrel Monkey Breeding and Research Resource" (SMBRR), P40-RR01254. The SMBRR is the only NIH supported national resource for a Neotropical primate genus (New World Monkey). The proposed owl monkey resource and resource- related research program will complement the current research resource program by the addition of a second Neotropical primate genus of biomedical research importance. This additional resource will help to meet the needs of the National Institute for Allergy and Infectious Disease's intramural malaria research program and serve the extramural research community by providing owl monkeys of known genetic background, tissues, cell lines and biological fluids from owl monkeys, and a registry of normal values and reagents that can be used in studies that utilize owl monkeys. This will be the only such resource for owl monkeys available to the NIH extramural grantee community and will expand the mission of the SMBRR to a second New World monkey genus. The initial establishment of this research resource can be accomplished rapidly by integrating it into the existing national research resource infrastructure that has been developed at the SMBRR over the past 23 years. The longer-term goal, to create a self-sustaining breeding resource of owl monkeys, will be accomplished by applying expertise that has been developed at the SMBRR for squirrel monkeys with resource-related research that specifically focuses on reducing adult mortality and improving reproductive efficiency of the owl monkey. This project will help to address the need for resources of alternative primate species to reduce the demand for rhesus monkeys that are in critically short supply.